1. Field of the Invention
The present invention relates to a system and method for scanning edges of a workpiece.
2. Description of Related Art
Measurement is an important phase in the production process. It is closely interrelated to the quality of the production. In ordinary measurement technology, some people use a charge coupled device (CCD) or a contact-measure method to measure ball grid array (BGA) objects and three-dimensional objects. Some other people use an image measure machine within a CCD to measure the BGA objects and the three-dimensional objects, and convert images captured by the CCD into data files. If actual sizes of the objects are very small, the images captured by the CCD should larger than the actual sizes of the objects in order to insure the measurement precision of the objects.
When the image measure machine measures a workpiece, the CCD captures images of the workpiece firstly, and then a user edits a program to scan the images of the workpiece. The CCD has a focusing, which has a fixed capture spectrum, can only capture images limited to part of the workpiece. If the user wants to scan an overview image of the whole workpiece in one plane, the program is required to be edited preliminarily, and there may be some errors in editing the program.
What is needed, therefore, is a system and method for scanning edges of the workpiece automatically in the plane.